Hillbrook sales offers a handy vibration meter, type vm-301. This is a lightweight hand held, battery-operated instrument for vibration measurement. The unit has a charge amplifier input stage, which permits use of long accelerometer cables. Integrator stages following the amplifier facilitate measurement of velocity and displacement. In combination with the accelerometer type pg 101 the unit provides direct readout of vibration parameters on a 31/2 digits lcd display. An internal 9 v battery powers the unit. To conserve battery life an auto shut off circuit having a period of 60 seconds is provided. As the weight of the pick up is only 30 gm and the instrument only 300 gm, these are very handy and small, powered by batteries to be taken to any place for measurements. Measurement ranges: acceleration 0.1 -199-9 m/s2; peak velocity 0.01-19.99 cm/s rms; displacement - 0.001 - 1.999 mm pp; and frequency range 10 hz to 1 khz.
